Test Doubles: When to Use Mock vs Stub vs Fake
Gerard Meszaros coined the term ’test double’ in his book xUnit Test Patterns to describe any object that stands in for a real dependency during testing. The film industry calls them stunt…
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Rust Mocking: mockall and Mock Traits
Mocking in Rust is fundamentally different from dynamic languages. You can’t monkey-patch methods or swap implementations at runtime. Rust’s static typing and ownership rules make the patterns you’d…
Read more →JavaScript Mock Functions: jest.fn() and vi.fn()
Unit testing means testing code in isolation. But real code has dependencies—API clients, databases, file systems, third-party services. You don’t want your unit tests making actual HTTP requests or…
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